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------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- S Y S T E M . V A L _ B O O L --
-- --
-- S p e c --
-- --
-- Copyright (C) 1992-2024, Free Software Foundation, Inc. --
-- --
-- GNAT is free software; you can redistribute it and/or modify it under --
-- terms of the GNU General Public License as published by the Free Soft- --
-- ware Foundation; either version 3, or (at your option) any later ver- --
-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE. --
-- --
-- As a special exception under Section 7 of GPL version 3, you are granted --
-- additional permissions described in the GCC Runtime Library Exception, --
-- version 3.1, as published by the Free Software Foundation. --
-- --
-- You should have received a copy of the GNU General Public License and --
-- a copy of the GCC Runtime Library Exception along with this program; --
-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
-- <http://www.gnu.org/licenses/>. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
-- Preconditions in this unit are meant for analysis only, not for run-time
-- checking, so that the expected exceptions are raised. This is enforced by
-- setting the corresponding assertion policy to Ignore. Postconditions and
-- contract cases should not be executed at runtime as well, in order not to
-- slow down the execution of these functions.
pragma Assertion_Policy (Pre => Ignore,
Post => Ignore,
Contract_Cases => Ignore,
Ghost => Ignore);
with System.Val_Spec;
package System.Val_Bool
with SPARK_Mode
is
pragma Preelaborate;
function Value_Boolean (Str : String) return Boolean
with
Pre => System.Val_Spec.Is_Boolean_Image_Ghost (Str, True)
or else System.Val_Spec.Is_Boolean_Image_Ghost (Str, False),
Post =>
Value_Boolean'Result =
(Str (System.Val_Spec.First_Non_Space_Ghost
(Str, Str'First, Str'Last)) in 't' | 'T');
-- Computes Boolean'Value (Str)
end System.Val_Bool;
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